I was able to finesse an early novel project into #FadeIn, but let me tell you, going from LibreOffice to Fade In with the novel plugin takes some doing. First saved it as .RTF, had to go back and fix all the fancy quotes, then used RTF2BBCode, then massaged that manually into Fountain format in Notepad++ and cleaned up a mess that LibreOffice left in the formatting, then Fountain didn't even import properly, so more cleaning. There was cleanup at every step. And even after that all the ellipses got lost, so I had to manually find them as a control character in Notepad++ and replace them with triple periods and from there is was just easier to manually add them.
Being honest, what I actually write in looks quite a bit more like Fountain format. That said... Last night I kind of just hated how it looked in novel format, couldn't read it properly, and felt it was too much like a paper to be marked up, but I came around to it this morning. I feel like the limits will make my writing better.